Pure Web Audio, zero deps (site/decks.js, self-contained UI):
- deck A/B with waveform (client-computed peaks), click-to-seek, play/pause, CUE
- ±8% varispeed pitch (playbackRate — turntable behaviour, deliberately no keylock)
- channel gains + equal-power crossfader, DynamicsCompressor master limiter
- AudioContext lazily created on first load (autoplay policy safe)
Sources:
- local preview MP3s: PREVIEWS_DIR (default ./previews, gitignored) served at
/previews, discovered via GET /shop/local-previews/{release_id}
({release_id}.mp3 / {release_id}-*.mp3|.m4a); on prod bind-mount the collection
- Apple 30s previews: GET /shop/preview-proxy?u= (STRICT whitelist
*.itunes.apple.com / *.mzstatic.com) — Apple CDN sends no CORS, Web Audio needs it
- YouTube/Beatport/Bandcamp embeds untouched: iframes can never enter a mixer
release.html: A/B load buttons per track preview + local-cut rows.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>